JPS5968361A - Rigid resin composition - Google Patents

Abstract

PURPOSE:To provide a rigid resin compsn. accepting extensive processing conditions, yielding high impact strength and excellent weatherability, by mixing a particular graft copolymer, chlorinated polyethylene and, if necessary, PE with PVC in specific amts. CONSTITUTION:A rigid resin compsn. is obtained by mixing 5-30pts.wt. graft copolymer (A) giving by polymn. of 30-80wt% ethylene/vinyl ester copolymer or ethylene/acrylate ester copolymer and 70-20wt% vinyl chloride or a monomeric mixture consisting mainly of vinyl chloride, 2-15pts.wt. chlorinated PE (B), and 0-25pts.wt. PE with 100pts.wt. PVC, and satisfying the relationships I and II[wherein a, b, and c are the wt. of A, B, and C used, respectively; Cl2 (b) is the wt. of chlorine in b]. Said compsn. accepts extensive processing conditions and has high impact strength and excellent weatherability.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hard resin composition that can be used under a wide range of processing conditions and that provides high impact strength and excellent weatherability.

Polyvinyl chloride (hereinafter referred to as PVC) is used in large quantities in construction, vehicles, etc. due to its excellent physical properties, flame retardance, chemical resistance, and weather resistance, as well as its economic efficiency. Many of these applications are used outdoors for long periods of time, and there are few products that require both high impact resistance and weather resistance.

Up to now, the following methods (11 to (4)) have been known as methods for improving the impact strength and weather resistance of PVC.

That is, b(1) ethylene-vinyl ester copolymer (E
VA), ethylene-acrylic ester copolymer (EE
A), a method f21EVA of mixing one or more types of di-stomers such as chlorinated polyolefins (CPE) with PvC,
EEA, CPE, x-propylene copolymer (EP
R), ethylene-propylene-nonconjugated diene copolymer (
EPT), butyl rubber or its chlorinated product (IIR
), epichlorohydrin rubber (CUa), (meth)acrylic acid ester-based copolymers (AR), or polyolefins (PE). Method of using polymer obtained by polymerization, (3) EVA, EEA, EPR, EPT
, I IL CHR, CPE, AR.

A polymer obtained by polymerizing vinyl chloride in the presence of PE etc.
Method of VIC mixing, (4) EVA%EEA.

Polymerizing one or more polymerizable monomers selected from (meth)acrylic esters, aromatic vinyl compounds, and vinyl cyanide compounds in the presence of EPT, EPRlI IR, CPJ AR, PE, etc. A method of mixing the obtained polymer and PVC is known.

However, these conventional methods have many problems in actual processing and use, and the current situation is that they are not necessarily of a level 1 that satisfies users.

In other words, in method (1), in order to improve impact resistance, an elastomer that is semi-compatible with PVC is used, so under normal cross-wire conditions, dispersion is insufficient and no reinforcing effect appears. There are many things. On the other hand, it is possible to use a type of elastomer that is highly compatible with PvC, but in this case, not only will the impact resistance strength be reduced, but the hardness of the product will also be reduced. Furthermore, according to this method, the softening temperature of the mixture is significantly lowered, so that it is necessary to limit the use temperature of the product to a low level.

Further, in examples using EVA, the effect of improving impact strength is small, and in examples using CPE, weather resistance stability is poor.

Although weather resistance stability and impact strength can be improved by using both in combination, a decrease in the softening temperature is unavoidable.

+2) (') In the case of a special product (using EVA, Ishi, EA or EPR with a nitrogen stomer), a part of the elastomer is likely to be commercialized. PV
Since the polymer is chemically bonded to PvC and becomes a homogeneous dispersion of PvC and elastomer, it has the advantage that products with high impact values can be easily obtained, and the elastomer ratio in the polymer is also low. It can be made small, has a small drop in value temperature, and has excellent weather resistance. However, this polymer has the problem of a narrow processing range in which the impact strength suddenly decreases even if the processing time is slightly longer or the heating temperature is slightly increased. In order to obtain the polymer as a powder that is easy to mix with various compounding agents similar to ordinary PVC, it is necessary to dissolve the nidistomer in vinyl chloride or to pulverize it during polymerization, making single polymerization complicated.

According to method (3), it is possible to achieve excellent dispersibility between PVC and elastomer more economically than method (2), and there are commercial examples of products using EVA as the elastomer. many. However, the narrow processing width remains the biggest problem with this method as well.

In method (4), an emulsion of AR is used as an elastomer, and a powdery polymer obtained by polymerizing the monomer in one or multiple stages in the presence of is commercialized as an acrylate impact additive. There are many examples where this is done. According to this method, since the mixture can be processed over a wide range, it is possible to stably produce products with high impact strength, and the softening temperature decreases little, but the weather resistance stability of impact strength is not necessarily sufficient. (・. Another problem with this method is that the impact strength changes significantly depending on the shape of the notch.

The inventor of the present invention has conducted extensive studies on the conventional methods for obtaining weather-resistant and impact-resistant resin products, as described below, and found that the narrow processing width of method (3), which inherently has false weather resistance. As a result of research on methods to improve the process, we have found that it is possible to provide PVC resin products that can be stably molded under a wide range of processing conditions, have good weather resistance, and have a high softening temperature. We found a composition that could do this, and completed the present invention.

That is, according to the present invention, ethylene-vinyl ester copolymer (EVA) or ethylene-acrylic acid ester copolymer (EEA) is mixed with 30-80 g of vinyl chloride or a phosphor mixture mainly composed of vinyl chloride with 70-20 g of ethylene-vinyl ester copolymer (EVA) or ethylene-acrylic acid ester copolymer (EEA). 5 to 30 parts by weight of graft copolymer (A), 2 to 15 parts by weight of chlorinated polyethylene (CPE) (B) and 100 parts by weight of polyethylene (C1O to 25 parts by weight) of polyvinyl chloride (PVC). parts by weight, and the formula b + co, 1 < - < 1 (where a, h, and C are respectively (A+, (+3), (C
A rigid resin composition is provided, which is characterized in that it has a heavy chlorine content and leaks Cl, (h) is a chlorine heavy chain in b.

The graft copolymer (A) in the present invention can be produced by a conventional method. EVA or EEA having an ethylene content of 20 to 8 (by weight) is used. If the amount of ethylene is less than 20%, the glass transition point will be too high and the impact strength will not be sufficiently developed.
If it exceeds this amount, the compatibility with vinyl chloride becomes poor. EVA
Examples of vinyl esters in EEA include vinyl acetate, vinyl propionate, vinyl laurate, etc. Examples of acrylic esters in EEA include methyl acrylate, ethyl acrylate, butyl acrylate.

Examples include hydroxyethyl acrylate, hydroxypropyl acrylate, 2-ethylhexyl acrylate, and the like. A copolymer of carbon monoxide, vinyl ether, olefin other than ethylene, etc. may be used as a third component together with these vinyl esters and acrylic esters. Conventional co-integrable weights can be used with the vinyl chloride polymerized in the presence of EVA or EEA, if desired, in the range of up to 30 g, in mixtures with the vinyl chloride. Examples include (i) monoolefins, vinyl ethers, (meth)acrylates, vinyl esters, unsaturated acids, and the like.

p on one side in the graft copolymer: V A or EEA
7. It is necessary for 11 to be an arrow of 30 to 80 weights. If this ratio is less than 30% by weight, the impact strength improvement effect of PVC is insufficient, and if it exceeds 80% by weight,
The increased tackiness causes many problems in the production and processing of the graft copolymer, and the dispersibility in PVC decreases.

CPF in the present invention: (B) is an ethylene homopolymer or a copolymer of ethylene with 15% by weight or less of other monomers produced by a high pressure, medium pressure or low pressure method (preferably a same pressure method). It is obtained by chlorinating a powder in suspension in water or in gaseous chlorine.

Its molecular weight is usually IQ000-500,000,
Moreover, the chlorine content is 5 to 49% by weight. Chlorine content is 5
If it is less than % by weight, the compatibility with PVC is poor; on the other hand,
If it exceeds 49% by weight, the compatibility becomes too large and it becomes too hard, so that there is no effect of improving impact resistance.

Polyethylene (C) has a density of 0.91 to 0.9
Low-density polyethylene with a rating of 41/crd is good.

Tart index at 190℃ from 0.1 to 25
A certain degree may be used as desired.

In the present invention, the PVC used in conjunction with (A), (B), and (C) above is not particularly limited as long as it is used for ordinary building materials and hard products, but it is usually a vinyl chloride homopolymer or A copolymer of 80 weight or more of vinyl chloride and 20 weight or less of a monomer copolymerizable with vinyl chloride, or a chlorinated product thereof, with an average degree of polymerization of 400 to 1500 as measured by the method of JIS K6721. A certain degree is used.

If the average degree of polymerization is less than 400, the processability is excellent, but the impact resistance is low, and if it is greater than 11,500, the processability is poor.

The amounts of (A), (Bl, and (C) used per 100 parts by weight of PVC are (A) 5 to 30 parts by weight, (B) 2 to 15 parts by weight, and (C) 0 to 25 parts by weight. If (A) is less than 5 parts by weight, the weather resistance retention power will not be sufficient, and if it is more than 30 parts by weight, the softening point will be significantly lowered.Also, if (B)
If the width is less than 2 times, the effect of improving the machining width will not be realized, and 1
If the amount exceeds 5 parts by weight, there will be a deterioration in appearance called chalking and discoloration will be significant, and the softening point will also be significantly lowered. If (C) exceeds 25 parts by weight, impact resistance will not be exhibited under relatively gentle kneading processing conditions, and the object of the present invention, which is to expand the processing width, cannot be achieved.

The amount of each component used in the present invention is defined as described above, but it is also necessary to satisfy the following formulas (1) and (2).

b −) −c 0.1 (preferably 0.3: K −< 1
(If Formula 21 (1) is not satisfied, that is, if the weight of chlorine derived from CPH is less than 5% by weight in the total weight of CPE and polyethylene used, the ratio of components incompatible with PVC will be too large. Because the gelation of the composition is delayed, sufficient impact strength cannot be developed unless processing is performed at relatively high temperatures and for a long time.On the other hand, when the thickness exceeds 40, (B) and (C) are used. However, even slight changes in processing conditions can cause significant changes in impact resistance, making it difficult to obtain products with stable quality.

In addition, if formula (2) is not satisfied, that is, the total weight of CPE and polyethylene is 10% of the weight of the graft copolymer.
If it is less than 1/2, the stability of the machining width is insufficient (A)
There is no advantage compared to using it alone. On the other hand, if the value is equal to or higher, the compatibility with PVC will decrease, so impact resistance will not be achieved under normal cross-wire conditions, and the purpose of the present invention, which is to expand the processing width, will not be achieved. This will impede the excellent weather resistance of the mixed system with the graft copolymer.

Furthermore, due to the presence of the non-chlorinated portion of CPE (and polyethylene), PVC is removed during the molding process of the composition.
It is possible to maintain the phase structure formed by a portion of the nitrogen and the graft copolymer, and as a result, it is thought that the processing range of the composition will be expanded.

In the present invention, for PVC (A), CB), F
By using a polymethyl methacrylate polymer as desired together with the C+ component, it is possible to further prevent heat deformability of the composition and improve vacuum formability. The amount of star used is 0 to 5 parts by weight, preferably 1 to 3 parts by weight per 100 parts of PVC. As a specific example, methyl methacrylate is the main ingredient, and (meth)
Acrylic acid esters, aromatic vinyl compounds, vinyl cyanide compounds, etc. (in some cases, a small amount of polyfunctional acrylic acid monomers having two or more unsaturated bonds, allyl compounds, etc. may be allowed to coexist). Examples include polymers having a gel content of less than 500% by weight, which are obtained by one-stage or multi-stage emulsion copolymerization. Preferably, a polymer in which 50% by weight or more of the non-gel portion has a molecular weight of 10QOOO or more, or a block copolymer in which at least one component is methyl methacrylate. Some of them are commercialized as processing aids and lubricants.

It goes without saying that the composition of the present invention may further contain conventional plasticizers, stabilizers, lubricants, pigments, fillers, etc., if necessary. Molding of this composition can be carried out by a conventional method, but in this case, processing conditions can be selected widely.
It is possible.

In addition, the obtained molded product exhibits excellent weather resistance, impact resistance, and heat resistance, and is therefore highly useful as general hard products such as construction materials, vehicles, agricultural and fisheries assets, etc.

In addition, the composition itself of the graft copolymer and CPE in the present invention is
11 etc., these have a low softening temperature,
The purpose of the composition of the present invention is to obtain a rubber-like product that has a soft texture at room temperature.
By blending (A), (B), and optionally (C) in small amounts in specific proportions with c, a hard product with excellent stiffness properties can be obtained. Therefore, the two have completely different technical ideas and structures.

Next, the present invention will be explained by examples. Note that the number of copies and staff are based on @quantity.

Example 1 Table 1 ((The ingredients shown in the indicated weight ratios were mixed using a mill roll at 170"C for 3 minutes (mixing condition I) at 180°
Mix at C for 10 minutes (mixing condition +r) or at +70"C for 6 minutes (mixing condition ■) to form a sheet,
``Trial autosheets of three thicknesses were made by pressing for 5 minutes at C.

This sample has impact strength (JISK-7111) and hardness (JISK-7111) and hardness (JISK-7111)
IS K-7202), softening temperature (JIS K-6745
Softness temperature test 1 @ method ((semi-J'ru)), weather resistance [for items with high impact strength, impact strength is increased by weatherometer and outdoor exposure JISK-71, 11), color tone change (visual observation), presence or absence of chalking. (visual observation)] was measured. The results are shown in Table 1.

Example 2 50 parts of polyvinyl chloride with an average degree of polymerization of 1050, chlorine content of 67 parts, 50 parts of chlorinated polyvinyl chloride with an average degree of polymerization of 700
16.7 parts of a graft copolymer obtained by polymerizing 55 parts of vinyl chloride to 45 parts of ethylene/ethyl acrylate (polymerization ratio of 75,725) copolymer, 6.7 parts of amorphous chlorinated polyethylene with a chlorine content of 35%. 7 parts, 3.3 parts of powdered polyethylene with a density o, 92 g/F melt index 4, 4 parts of methyl methacrylate-styrene block copolymer with a molded average molecular weight of 60 QOOO and methyl methacrylate in a ratio of 50. Mix in the same manner as in Example 1,
A sample was obtained by pressing. The results are as follows.

Mixing conditions I II Impact strength during regular attack kg・σ/d) 98 105 Hardness 110 115
Softening temperature ("C) 75 81 Impact strength after 000 hours KLCRN/I) 79 81 Color change None None Chalking None None Impact strength after 6 months of outdoor exposure kg・(COL/CRL) s 4
92 Color tone change None None Chalking None None Example 3 In place of the vinyl chloride homopolymer of Example 1, a vinyl chloride-vinyl acetate copolymer (average degree of polymerization 850) containing 4 units of vinyl acetate was used, and In place of the methyl methacrylate-based polymer of Example 1, a terpolymer containing 48% methyl methacrylate component and the remainder styrene and butyl acrylate (weight ratio of 54 inches with a molecular weight of 10QOOO or more, gel content of 4 inches) was used. A sample was obtained by the same procedure as in Example 1 except for the use of the following. The results are as follows.

Mixing conditions I It normal impact strength k1cm/cm) 129 135
Hardness 93 97 Softening temperature (c) 59 64 000 hours impact strength kg・m/i) 92 97
Color change: Slight Chalking None None After 6 months of outdoor exposure

Claims (1)

[Claims] 30 to 80 parts by weight of an ethylene-vinyl ester copolymer or an ethylene-acrylic ester copolymer is polymerized with 70 to 20 parts by weight of vinyl chloride or a monodisperse mixture mainly composed of vinyl chloride. 5 to 30 parts by weight of the graft copolymer (A), 2 to 15 parts by weight of chlorinated polyethylene (B), and 0 to 25 parts by weight of polyethylene (C) to 100 parts by weight of polyvinyl chloride.
(in the formula, a, b, and c are (A), (B), and (C), respectively)
, and C1t (b) is the weight of chlorine in b).